Winterising your boat’s Electrics and Electronics

Written by Derek Gilbert on December 7, 2018 at 4:25 pm

With winter upon us we have some tips to help prepare your boat for the months ahead:

Where possible, remove batteries and keep them warm and dry over the winter – if you are unable to do this, ask your local approved and qualified marine electrician to do this, ( for a list of BMEEA members able to assist please visit the member locator)

Keep batteries fully charged or topped up at least every couple of months. Batteries left uncharged for long periods may need to be replaced completely. If you’re unable to remove batteries or if the boat is staying on its mooring, leave them fully topped up and regularly recharged, as full batteries are less likely to freeze in sub-zero temperatures.

Damp is the enemy of every electrical and electronic system, ensure the boat is well ventilated or installed with a dehumidifier.

Equipment left unused for extended periods of time can become erratic in operation due to damp affecting switch contacts, internal circuit boards, signal processors or even computer chips, so regular power up checks and operation during extended idle periods can help maintain correct operation

Switch contacts can accumulate Verdigris over extended idle periods and this can create high resistance connections or even complete isolation of switch contacts. Regular operation of the switches can slow down the deterioration of switch contact surfaces.

Do not spray the switch gear with corrosion inhibitors, this can leave a residue which effectively isolates the contact surfaces and creates a malfunctioning switch.

Carefully check all cables and Junction boxes to ensure the cable insulation is not damaged, cables are secured to bulkheads and not showing any signs of chafing, ensure all junction boxes are securely mounted and correctly sealed and no cables or junction boxes are mounted such that they remain submerged for extended periods of time.